Skip to main content
New! BOOM Notices and Schema v7.0.0. See news and announcements

GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

44495 results found.

  1. IPN triangulation of GRB021109 (portion of annulus)
  2. IPN triangulation of GRB021113 (=H2449; annulus)
  3. IPN triangulation of GRB021108 (CORRECTION; TWO LARGE ERROR BOXES)
  4. GRB 021113: Optical observations
  5. GRB 021112: RAPTOR Observations
  6. GRB 021113: Optical Observations
  7. GRB 021113: Optical Observations
  8. GRB021113 (=H2449): A Long GRB Localized by HETE
  9. GRB 021112: Optical Observations
  10. GRB 021112: R-band search
  11. IPN triangulation of GRB021108 (large error box)
  12. GRB021112 (=H2448): A Long GRB Localized by HETE
  13. GRB 021016: Optical Observations
  14. IPN triangulation of GRB021109 (annulus)
  15. IPN triangulation of GRB021108 (annulus)
  16. GRB021004: Near infrared spectroscopy
  17. GRB021104: Optical Observations
  18. IPN triangulation of GRB021104 (annulus)
  19. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  20. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  21. SGR1900+14 activity, November 2-4, 2002
  22. Spectropolarimetry of GRB021004
  23. GRB021104: Optical observations
  24. GRB021104: optical observations
  25. GRB021104: Candidate present in DSS
  26. GRB021104: possible optical afterglow
  27. IPN triangulation of GRB021102 (annulus)
  28. Detection of activity from SGR 1900+14 with the RXTE/PCA
  29. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  30. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  31. IPN triangulation of GRB021025 (portion of annulus)
  32. IPN triangulation of GRB021027 (single large error box)
  33. GRB021004, late-time optical observations
  34. IPN triangulation of GRB021027 (two large error boxes)
  35. GRB 021023: Infrared Imaging
  36. IPN triangulation of GRB021027 (annulus)
  37. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  38. IPN triangulation of GRB021025 (annulus)
  39. IPN triangulation of SGR1900+14, October 22 2002
  40. GRB 021004: optical observations
  41. IPN triangulation of GRB021023 (small error boc)
  42. GRB021004: Optical Observations
  43. GRB 020813; likely host galaxy.
  44. IPN triangulation of GRB021020 (smaller error box)
  45. GRB021021(=XRF 021021): An X-ray Flash Localized by HETE
  46. IPN triangulation of GRB021020
  47. GRB 021008, radio observations
  48. GRB 021016, optical observations
  49. GRB 021004: VRI observations at TNG: possible break
  50. GRB021016, optical observations
  51. SGR1900+14: burst on October 10 2002
  52. GRB 021008, optical observations
  53. GRB021016(=H2397): A Long GRB Localized by HETE
  54. IPN triangulation of GRB021016 (area corrected)
  55. IPN triangulation of GRB021016 (small error box)
  56. GRB021004: Optical Observations
  57. IPN triangulation of GRB021014 (large error box)
  58. IPN triangulation of GRB021013 (single error box)
  59. GRB 021004: optical spectroscopy on Oct 11
  60. IPN triangulation of GRB021013 (two small error boxes)
  61. GRB021004: High-resolution optical spectroscopy
  62. IPN triangulation of GRB021013 (annulus)
  63. XRF 020903: flattening of the optical light curve.
  64. GRB021004, UBVRcIc field photometry update
  65. IPN triangulation of GRB021008 (single error box)
  66. GRB021004: Optical Observations
  67. GRB 021004 submm observations
  68. IPN triangulation of GRB021008B (annulus)
  69. IPN triangulation of GRB021008 (two small error boxes)
  70. GRB021004 Chandra HETG Observations
  71. GRB 021004: Optical/NIR Observations
  72. GRB 021004: Additional V-band Polarimetric Observations
  73. GRB021004: optical observation
  74. GRB 021004: Host Galaxy Star Formation Rate
  75. GRB 021004 submm observations
  76. GRB 021004: WC wind?
  77. IPN triangulation of GRB021008
  78. GRB021004: NIR and Optical observations
  79. GRB 021004: Optical measurement at OHP
  80. GRB 021004: Optical observations, AUDE network
  81. GRB 021004 - VLA Radio Observations
  82. GRB 021004 - Unusual Radio-to-Submm Spectrum
  83. GRB 021004: optical spectroscopy
  84. IPN triangulation of GRB021007 (annulus)
  85. XRF 020903 spectrum
  86. GRB 021004: HST/STIS spectroscopic observations
  87. GRB021004: optical observations and predicted break time
  88. GRB021004: BVRc photometry
  89. GRB 021004 redshift
  90. GRB021004 radio observation
  91. GRB021004: restart of optical decay
  92. GRB 021004: Optical Decay
  93. GRB 021004 continued IR fading
  94. HETE fluences for GRB021004
  95. GRB 021004, spectroscopic observations
  96. GRB021004: not fading anymore?
  97. GRB 021004: Optical Photometry at 2.5 Days
  98. GRB 021004: polarimetric observations
  99. GRB 021004: V-band Polarimetric Observations
  100. GRB021004: Update Bisei photometric data

Advanced

Download all Circulars as a .tar.gz archive:
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov